Enhancement of grayscale image display with amplitude Fourier holograms, employing a limited bandwidth phase
Journal
Applied Optics
ISSN
1559-128X
2155-3165
Date Issued
2022
Type
text::journal::journal article
Abstract
<jats:p>An alternative method is proposed to generate a modified
random phase that is able to
concentrate the light around a given direction, produces
well-contrasted Fourier amplitude holograms, reduces the quantity and
the randomness of the speckle noise in the image, and decreases the
amount of data necessary for the phase definition. This modified
limited bandwidth random phase uses structured random phase patterns
to control the object dispersion. The resulting hologram displays an
image with structured speckle noise (SSN), exhibiting similar metrics
as the iterative method for hologram generation. A filtering process
eliminates the SSN; the speckle contrast in the final image is reduced
from 0.66 to 0.07; and the peak SNR increases from 7.21 dB to
12.62 dB. This method enhances the fine details and grayscale tone
perception in the final image.</jats:p>
random phase that is able to
concentrate the light around a given direction, produces
well-contrasted Fourier amplitude holograms, reduces the quantity and
the randomness of the speckle noise in the image, and decreases the
amount of data necessary for the phase definition. This modified
limited bandwidth random phase uses structured random phase patterns
to control the object dispersion. The resulting hologram displays an
image with structured speckle noise (SSN), exhibiting similar metrics
as the iterative method for hologram generation. A filtering process
eliminates the SSN; the speckle contrast in the final image is reduced
from 0.66 to 0.07; and the peak SNR increases from 7.21 dB to
12.62 dB. This method enhances the fine details and grayscale tone
perception in the final image.</jats:p>